Asynchronous contact printer for motion picture film

Abstract

An asynchronous contact printer and a related method for printing motion picture film in different formats. The contact printer has a pair of film drives that move duplicate film and original film at different increments through the printer, and then intermittently stop the film to permit exposure of the original onto the duplicate. The printer can print duplicate film in an alternate format, such as the three-perforation or 2.5-perforation format, from original film in another format, such as the four-perforation format. This is accomplished by moving the film asynchronously through the printer and exposing frames of the original film onto the duplicate film on a frame-by-frame basis.

We claim: 
     
       1. A method of printing duplicate film from original film in a contact printer, comprising: separating a first platen of the contact printer from a second platen of the contact printer;   advancing original film across the first platen by a distance substantially equal to one frame, wherein the original film has a first format having frames spanning a first pre-determined number of perforations;   advancing unexposed duplicate film across the second platen by a distance corresponding to a selected number of perforations;   stopping advancement of the original film when said one frame is registered with respect to an aperture of the contact printer;   stopping advancement of the duplicate film when it has advanced by said distance corresponding to said selected number of perforations;   bringing the first and second platens together to thereby bring the original film and the duplicate film into contact with each other; and   exposing an image from said one frame of the original film onto the duplicate film, to thereby create duplicate film in a second format having frames spanning a second pre-determined number of perforations.   
     
     
       2. The method of claim 1, further comprising: separating the duplicate film and the original film during their advancement through the printer; and   bringing the original film and the duplicate film into contact with each other when the advancement of the original film and the duplicate film has stopped.   
     
     
       3. The method of claim 1, wherein the duplicate film is advanced through the printer by a distance corresponding to three perforations each time the original film is advanced by one frame. 
     
     
       4. The method of claim 1, wherein the duplicate film is advanced through the printer by a distance corresponding to 2.5 perforations each time the original film is advanced by one frame. 
     
     
       5. The method of claim 1, wherein the duplicate film is advanced through the printer by a distance corresponding to four perforations each time the original film is advanced by one frame. 
     
     
       6. The method of claim 1, wherein the first format of the original film comprises a format in which each frame spans four perforations. 
     
     
       7. The method of claim 1, wherein the second format of the duplicate film comprises a format in which each frame spans three perforations. 
     
     
       8. The method of claim 1, wherein the second format of the duplicate film comprises a format in which each frame spans 2.5 perforations. 
     
     
       9. The method of claim 1, further comprising applying vacuum to bring the duplicate film into contact with the second platen and to bring the original film into contact with the first platen when advancement of said film has stopped and said platens are separated from each other. 
     
     
       10. The method of claim 9, wherein the vacuum is eliminated or applied in a reduced amount to the duplicate film and the original film during advancement through the printer, and wherein the vacuum is applied in an increased amount to the duplicate film and the original film when said advancement has stopped. 
     
     
       11. The method of claim 1, further comprising inserting a plurality of registration pins into the perforations of the duplicate film and the original film when advancement of the film has stopped. 
     
     
       12. The method of claim 2, wherein a film drive for advancing the duplicate film through the printer is mounted on a movable element, further comprising moving the movable element such that the duplicate film is moved away from and thereby substantially separated from the original film as the duplicate film and the original film are advanced through the printer. 
     
     
       13. The method of claim 12, further comprising moving the movable element such that the duplicate film moves toward the original film and thereby brings the duplicate film into contact with the original film when advancement of the duplicate film and the original film has stopped. 
     
     
       14. The method of claim 12, wherein the movable element comprises a pivot arm that is pivoted by operation of a cam. 
     
     
       15. The method of claim 1, further comprising operating a light source to expose the image from said one frame of the original film onto the duplicate film. 
     
     
       16. The method of claim 15, wherein the light source is reversible such that it can be moved to opposite sides of the printer. 
     
     
       17. A method of printing duplicate film in one format from original film in another format in a contact printer, wherein the original film has a first format having frames spanning a first pre-determined number of perforations, comprising: separating a first platen of the contact printer from a second platen of the contact printer;   advancing the original film across the first platen by a distance corresponding to one of said frames, while advancing unexposed duplicate film across the second platen by a distance corresponding to a selected number of perforations;   stopping advancement of the original film each time one of said frames is registered with respect to an aperture of the contact printer, while stopping advancement of the duplicate film each time it has advanced by said selected number of perforations;   applying sufficient vacuum to bring the original film into contact with the first platen and to bring the duplicate film into contact with the second platen and thereby substantially prevent movement of such film with respect to said platens when said platens are separated from each other;   bringing said platens together to thereby bring the original film and the duplicate film into contact with each other;   exposing images from said frames of the original film onto the duplicate film, each time the advancement of the original film and the duplicate film has stopped, to thereby create duplicate film in a second format having frames spanning a second pre-determined number of perforations; and   separating the platens and reducing the vacuum applied to the original film and the duplicate film to allow advancement of the original film across the first platen and advancement of the duplicate film across the second platen.   
     
     
       18. An asynchronous contact printer for printing duplicate film from original film, wherein the original film has a first format having frames spanning a first pre-determined number of perforations, comprising: a first film drive that intermittently advances the original film across a first platen, and that stops advancement of the original film each time one of its frames is registered with respect to an aperture in the printer;   a second film drive that intermittently advances the duplicate film across a second platen, and that stops the duplicate film each time it has advanced by a distance corresponding to a selected number of perforations;   an actuator that separates the first platen from the second platen and that returns first platen back together with the second platen; and   a light in substantial alignment with respect to the aperture that is selectively operable to expose images from said frames of the original film onto the duplicate film, to thereby create duplicate film in a second format having frames spanning a second pre-determined number of perforations.   
     
     
       19. The asynchronous contact printer of claim 18, further comprising: an arm on which the first platen is mounted; and   an actuator that moves the arm and thus moves the first platen away from the second platen, and that returns the arm and thus brings the first platen back together with the second platen.   
     
     
       20. The asynchronous contact printer of claim 19, wherein the arm comprises a pivot arm that pivots the first platen with respect to the second platen, and wherein the actuator comprises a cam that causes pivoting movement of the pivot arm. 
     
     
       21. The asynchronous contact printer of claim 20, further comprising a stepping motor for operating the cam. 
     
     
       22. The asynchronous contact printer of claim 20, further comprising a biasing element for normally biasing the pivot arm against pivoting movement. 
     
     
       23. The asynchronous contact printer of claim 22, wherein the biasing element comprises a spring. 
     
     
       24. The asynchronous contact printer of claim 18, further comprising vacuum ports in each of the first and second platens that apply vacuum to the original film and the duplicate film. 
     
     
       25. The asynchronous contact printer of claim 24, wherein vacuum is created in the vacuum ports by a vacuum tank that can be regulated to eliminate or apply reduced vacuum during advancement of the duplicate film and the original film, and to apply increased vacuum when the advancement of the duplicate film and the original film has stopped. 
     
     
       26. The asynchronous contact printer of claim 18, further comprising first registration pins that register the original film with respect to the aperture when advancement of the original film has stopped. 
     
     
       27. The asynchronous contact printer of claim 26, further comprising second registration pins that register the duplicate film with respect to the original film when advancement of the duplicate film has stopped. 
     
     
       28. The asynchronous contact printer of claim 18, wherein the first format of the original film comprises a format in which each frame spans four perforations. 
     
     
       29. The asynchronous contact printer of claim 18, wherein the second format of the duplicate film comprises a format in which each frame spans three perforations. 
     
     
       30. The asynchronous contact printer of claim 18, wherein the second format of the duplicate film comprises a format in which each frame spans 2.5 perforations. 
     
     
       31. The asynchronous contact printer of claim 18, wherein the second format of the duplicate film comprises a format in which each frame spans four perforations. 
     
     
       32. The asynchronous contact printer of claim 18, further comprising a controller that controls and coordinates advancement of the original film and the duplicate film at different increments through the printer;   stopping of the original film and the duplicate film each time one of the frames of the original film is registered with the aperture and the duplicate film has advanced by said selected number of perforations; and   operation of the light to expose images from said frames of the original film onto the duplicate film.   
     
     
       33. The asynchronous contact printer of claim 18, wherein the light has a shutter that blocks illumination when the original film and the duplicate film are advancing through the printer, and that permits illumination when the advancement of the original film and the duplicate film has stopped. 
     
     
       34. An asynchronous contact printer for printing duplicate film from original film, wherein the original film has a first format having frames spanning a first pre-determined number of perforations, comprising: a first platen having an aperture;   a second platen;   a first film drive that intermittently advances the original film across the first platen, and that stops advancement of the original film each time one of its frames is registered with respect to the aperture;   a second film drive that intermittently advances the duplicate film across the second platen, and that stops the duplicate film after it has advanced by a distance corresponding to a selected number of perforations;   means for separating the first and second platens to substantially prevent contact between the original film and the duplicate film during advancement of the original film and the duplicate film by the first and second film drives;   means for bringing the first and second platens together to thereby bring the original film and the duplicate film into contact each time one of said frames of the original film is registered with respect to the aperture and advancement of the original film and the duplicate film by the first and second film drives has stopped; and   a light in substantial alignment with the aperture to expose images from said frames of the original film onto the duplicate film, when advancement of the original film and the duplicate film by the first and second film drives has stopped, to thereby create duplicate film in a second format having frames spanning a second predetermined number of perforations.   
     
     
       35. The asynchronous contact printer of claim 36, wherein: the first film drive comprises a first servomotor for intermittently registering the frames of the original film with respect to the aperture, and a first multispeed motor for feeding the original film to and taking it away from the first platen; and   the second film drive comprises a second servomotor for intermittently advancing the duplicate film, and a second multispeed motor for feeding the duplicate film to and taking it away from the second platen.   
     
     
       36. The asynchronous contact printer of claim 34, wherein the means for separating the first and second platens and the means for bringing said platens together comprises: an arm on which the first platen is mounted; and   an actuator that moves the arm and thus moves the first platen away from the second platen, and that returns the arm and thus allows the first platen to move back together with the second platen.   
     
     
       37. The asynchronous contact printer of claim 34, further comprising a stop pin that controls the amount of separation between the first and second platens when said platens are moved together. 
     
     
       38. The asynchronous contact printer of claim 34, wherein the stop pin has one end connected to a portion of the printer that supports the second platen and another end that is received in a registration hole on another portion of the printer that supports the first platen. 
     
     
       39. The asynchronous contact printer of claim 38, wherein the stop pin is adjustable to change the amount of separation between the first and second platens. 
     
     
       40. A method of printing duplicate film in one format from original film in another format in a contact printer, wherein the original film has a first format having frames spanning a first pre-determined number of perforations, comprising: separating a first platen of the contact printer from a second platen of the contact printer;   advancing the original film across the first platen by a distance corresponding to one of said frames, while advancing unexposed duplicate film across the second platen by a distance corresponding to a selected number of perforations;   stopping advancement of the original film each time one of said frames is registered with respect to an aperture of the contact printer, while stopping advancement of the duplicate film each time it has advanced by said selected number of perforations;   inserting registration pins into the perforations of the original film and duplicate film;   applying sufficient vacuum to bring the original film into contact with the first platen and to bring the duplicate film into contact with the second platen and thereby substantially prevent movement of such film with respect to said platens when said platens are separated from each other;   retracting the registration pins from the perforations of the original film and the duplicate film;   bringing said platens together to thereby bring the original film and the duplicate film into contact with each other;   exposing images from said frames of the original film onto the duplicate film, each time the advancement of the original film and the duplicate film has stopped, to thereby create duplicate film in a second format having frames spanning a second pre-determined number of perforations; and   separating the platens and reducing the vacuum applied to the original film and the duplicate film to allow advancement of the original film across the first platen and advancement of the duplicate film across the second platen.   
     
     
       41. An asynchronous contact printer for printing duplicate film from original film, wherein the original film has a first format having frames spanning a first pre-determined number of perforations, comprising: a first platen having an aperture;   a second platen;   a first film drive that intermittently advances the original film across the first platen, and that stops advancement of the original film each time one of its frames is registered with respect to the aperture;   a second film drive that intermittently advances the duplicate film across the second platen, and that stops advancement of the duplicate film after it has advanced by a distance corresponding to a selected number of perforations;   means for separating the first and second platens to substantially prevent contact between the original film and the duplicate film during advancement of the original film and the duplicate film by the first and second film drives;   means for bringing the first and second platens together to thereby bring the original film and the duplicate film into contact each time one of said frames of the original film is registered with respect to the aperture and advancement of the original film and the duplicate film by the first and second film drives has stopped;   a vacuum source;   vacuum ports in each of the first and second platens connected to the vacuum source for applying sufficient vacuum to bring the original film into contact with the first platen and to bring the duplicate film into contact with the second platen, and thereby substantially prevent movement of such film with respect to said platens when said platens are separated from each other and advancement of said film has stopped, and for reducing the vacuum applied to the original film and the duplicate film to allow advancement of such film across said platens; and   a light in substantial alignment with the aperture to expose images from said frames of the original film onto the duplicate film, when advancement of the original film and the duplicate film by the first and second film drives has stopped, to thereby create duplicate film in a second format having frames spanning a second pre-determined number of perforations.